1. Field of the Invention
This invention relates to a photographic material, more particularly, to a photographic material containing a reactive polymer having a pendant (wherein the word "pendant" means that a reactive group is present at a side chain of a polymer) active ester group.
2. Development of the Invention
It is known to incorporate various polymers in a photographic system as mordants, antistatic agents, neutralizing agents, thickeners and sensitizers. However, these polymers, particularly when they are water-soluble, diffuse from a coated layer to an adjacent layer(s) and can adversely affect the properties of a photographic film (e.g., increase fogging, lower sensitivity and cause dye image spreading). To prevent this, mordants are rendered non-diffusable by incorporating therein a functional group reactive with gelatin (as described in U.S. Pat. No. 3,625,694) or by incorporating therein a functional group that reacts with a crosslinking agent (as described in U.S. Pat. No. 3,859,096).
However, the reactivity of functional groups incorporated in mordants of this type is low and it has been difficult to provide non-diffusable mordants reaction with gelatin or a crosslinking agent before diffusion occurs.
Therefore, the development of polymers having incorporated therein a highly reactive functional group that quickly reacts with gelatin or a crosslinking agent to render the polymer non-diffusable has been long needed.
One technique is known to bind various photographic additives to certain polymers to thereby fix them in a layer where they are added or make them nondiffusable.
The term "photographic additives" as used herein means additives as are conventionally used in photographic systems such as dyes, dye precursors, development restrainers, development accelerators, couplers, developing agents, auxiliary developer agents, bleaching restrainers, bleaching accelerators, silver halide solvents, silver complexing agents, foggants, anti-foggants, chemical sensitizers, spectral sensitizers, desensitizers, hardening agents, hardening accelerators, gelatin and surfactants.
Reactive polymers have been used in diffusion transfer to fix a diffusing dye within a photographic element, e.g., mordants as described in U.S. Pat. Nos. 3,709,690, 3,898,088 and 3,958,995, will fix a dye in diffusion transfer, but these mordants are cationic and fix anionic dyes by mutual electrostatic interaction and their fixing ability is not always satisfactory in that it is reduced by water in the photographic system or decreased pH so that the fixed dye easily fades upon exposure to sunlight or fluorescent light.
To eliminate these defects, a mordant that will fix certain dyes via covalent bonds is described in Japanese Patent Application (OPI) No. 65033/79 (ther term "OPI" as used herein refers to a "published unexamined Japanese patent application"). While this mordant is a good mordant for the specific types of dyes described in Japanese Patent Application (OPI) Nos. 111628/74 and 4819/77, it is not applicable to other dyes. In addition, the mordant does not fix the dyes at a high enough speed and is difficult to synthesize.
Therefore, the development of a mordant which rapidly and positively fixes diffused dyes does not permit the fixed dye to fade upon exposure to light and which is easy to synthesize on a large scale has been desired in the art.
Further, most photographic materials contain gelatin as a component, e.g., a silver halide photosensitive emulsion layer, an emulsion protective lyaer, a filter layer, an intermediate layer, an antihalation layer, a backing layer, a subbing layer on film base and a baryta layer use gelatin as a primary component. These gelatin-containing light-sensitive materials are processed with various aqueous solutions at different pHs and/or temperatures, but a gelatin-containing layer untreated with a hardener has low resistance to water and is easily scratched after swelling in an aqueous solution, and, in an extreme case, a gelatin layer may even dissolve out in a processing solution having a temperature of 30.degree. C. or more.
A number of compounds are known to be effective for hardening gelatin and increasing the water resistance, heat resistance and scratch resistance of a gelatin layer and are known as hardening agents in the production of photographic materials. For example, inorganic compounds such as chrome alum and organic compounds such as aldehyde compounds such as formaldehyde and glutaraldehyde, compounds having an active halogen as described in U.S. Pat. No. 3,288,775, etc., compounds having a reactive ethylenically unsaturated group as described in U.S. Pat. No. 3,635,718, etc., aziridine compounds as described in U.S. Pat. No. 3,017,280, etc., epoxy compounds as described in U.S. Pat. No. 3,091,537, etc., and halogenocarboxyaldehyde such as mucochloric acid are known. However, these hardening agents have one or more of the following defects: they have an adverse effect on the properties of a photosensitive material (e.g., increase fogging, lower sensitivity or change gradation), cause "after-hardening" wherein the hardening effect changes upon extended storage, are not adequately dissolved in water and cause lack of uniformity of the additives dispersed in the photographic layer, lose their hardening effect depending upon the photographic accitive used therewith (e.g., a color coupler for color photosensitive materials), are unstable and do not keep long, or are difficult to synthesize in large quantities.
A hardener of low molecular weight as is frequently used in hardening gelatin also will diffuse in a gelatin layer so that it is impossible to control the degree of hardening of laminated gelatin layers on a film base. On the other hand, commonly used polymeric non-diffusable gelatin hardening agents such as dialdehyde starch and polyacrolein are not satisfactory for use in a photosensitive material because they have adverse effects on photographic characteristics, such as to increase fogging and lower sensitivity. The polymeric hardening agents described in U.S. Pat. No. 4,161,407--which have a vinyl sulfone group as an active group--cause after-hardening because they harden a gelatin layer only slowly and the degree of swelling Q (defined hereunder) canges with time. Therefore, the development of a hardening agent that rapidly hardens a gelatin layer and which does not have any adverse effect on photographic characteristics has long been desired in the art.